By the term "cage" as used herein is intended the usual dictionary meaning of a box or enclosure having openwork such as wires or bars for confining birds or animals. According to the present invention, the cage unit is particularly adapted for the confinement of animals. Further, in the instant case, the cage unit is of a generally rectangular although not necessarily square nature, as will be apparent from the disclosure hereinafter.
Innumerable such cage units and assemblies have been constructed and innumerable others have been proposed. Representative of such items, as revealed by a search in the U.S. Patent Office, are those of U.S. Pat. Nos. 1,179,703; 1,227,814; 1,812,598; 2,041,049; 2,640,460; 2,789,531; 2,892,562; 3,087,459; and 4,161,159.
These patents disclose animal and bird cage units and assemblies of various types, sizes, and shapes, the last patent involving stacked cages and a novel feeding device between cages, the '459 patent involving portable and stackable cages with five (5) solid walls, the '562 patent involving a foldable cage construction which is stackable, the '531 patent involving a collapsible cage for birds, the '460 patent involving an exercise cage for birds and animals involving a plurality of cylindrical units, the '049 patent involving a stacked collapsible chicken brooder arranged in battery form with each unit constituting a side of the battery, the '598 patent involving a stackable cage or coop structure, the '814 patent disclosing a collapsible or foldable bird cage, and the 1916 '703 patent disclosing a poultry coop or crate which could be knocked down but which in assembled form could be rigidly supported by a frame.
Although all of the previous animal cage structures accomplished their objectives to a greater or lesser extent, certain problems continue to haunt or plague those portions of industry which require the caging and proper hygienic care and maintenance of large numbers of animals, as for example when they are to be utilized for pharmacological or toxicological evaluation of drugs, poisons, inhalants, or other materials with which a human is likely to come into contact. Among the remaining problems are the elimination of wall-mounted cages to permit cleaning behind the backs of cages; the ability to dissemble the cages rapidly an conveniently for washing or storage; the ability to rapidly assemble or reassemble the cages from the individual elements comprising the same; the ability to conveniently remove feces and other animal waste from the immediate vicinity of the caged animal for maintaining maximum cleanliness and hygienic living conditions; and finally but foremost the ability to provide the animal with living conditions which are as wholesome as possible while in a caged situation and with ready access to the animal whenever desired, all of the foregoing with a minimum of inconvenience and economy. The animal cage industry has long awaited developments which would even partially fulfill these requirements, but few have been forthcoming.
The present invention is based upon the concept of a standard module or modulus and is accordingly considered to be a modular system, involving not only modular cage elements but modular cage units and modular cage assemblies which, when arranged according to the present invention and description, especially when suspended from modular frame units of the invention, go far toward solving at least partially all of the aforementioned problems which have previously been nearly insoluble, the cage unit and cage system or assembly of the present invention being particularly adapted for the hygienic containment of animals such as monkeys, beagles, and the like.